European football's governing body has warned the English and Russian federations that their teams could be disqualified from Euro 2016 if there is further violence by their supporters.
UEFA's threat on Sunday came after it began disciplinary proceedings against the Russian federation following ugly scenes inside Marseilles' Stade Velodrome stadium at the end of Saturday's 1-1 draw between England and Russia.
Masked Russian fans charged at England supporters, punching and kicking them, forcing some of them to scramble over barriers to escape.
England supporters, however, were at the heart of days of street clashes in Marseille's Old Port district, which also involved French and Russian fans and left at least 20 people injured.
UEFA said it was "disgusted" and would not hesitate to impose sanctions, including "the potential disqualification of their respective teams from the tournament, should such violence occur again.
"This kind of behaviour is totally unacceptable and has no place in football," UEFA said, adding that it would also investigate allegations of racist behaviour and the throwing of missiles and fireworks.
A decision on sanctions against Russia will be made on Tuesday.
|At least 20 people were injured during street clashes in Marseille [Jean-Paul Pelissier/Reuters]
The English Football Association responded by saying it treats the UEFA warning with the "utmost seriousness", while Russia’s football's governing body urged fans to "obey the law".
French Interior Minister Bernard Cazeneuve called for the two teams to be punished, describing the behaviour of fans as "barbaric".
READ MORE: English and Russian fans clash in Marseille
Speaking on Sunday, he said that he had asked the cities hosting Euro 2016 fixtures "to take all useful measures aimed at prohibiting the sale, consumption and transport of alcoholic drinks within sensitive areas on the eve and on days of matches and on days when fan zones are open."
Separately, French authorities in the city of Lille said on Sunday that two people were slightly injured during violence involving supporters from Germany and Ukraine.
Police intervened and restored calm after the incidents, regional authorities said in a statement.